野田 孝浩^{1, 2}, 熊田 卓^{1, 2}, 日比 敏男¹, 伊藤 益弘¹, 竹島 賢治^{1, 2}, 杉田 文芳^{1, 2}, 矢橋 俊丈^{1, 2}, 佐々 敏¹, 木村 得次¹, 中野 哲²

Takahiro NODA^{1, 2}, Takashi KUMADA^{1, 2}, Toshio HIBI¹, Masuhiro ITOH¹, Kenji TAKESHIMA^{1, 2}, Fumiyoshi SUGITA^{1, 2}, Toshitake YABASHI^{1, 2}, Toshi SASSA¹, Tokuji KIMURA¹, Satoshi NAKANO²

¹大垣市民病院超音波検査室, ²大垣市民病院消化器科

¹Division of Abdominal Ultrasound, Ogaki Municipal Hospital, ²Department of Gastroenterology, Ogaki Municipal Hospital

キーワード : CO<SUB>2</SUB> microbubbles, Enhanced ultrasonography, Subtraction, Hepatocellular carcinoma, Quantitative analysis

In contrast-enhancement ultrasonography (CEUS) with arterial injection of carbon dioxide microbubbles, it is difficult to evaluate degree of enhancement of hyperechoic or hypoechoic nodules using the criterion used in plain US, because degree of enhancement of each nodule compared with that of the surrounding liver parenchyma is judged visually in CEUS. We devised a new method for estimating vascularity of nodules in the liver from CEUS (USDSA) images. Here we evaluated the hemodynamic patterns of 51 nodules obtained using USDSA and compared the vascular patterns of 10 nodules that appeared hyperechoic in plain US images with results obtained with quantitative analysis. USDSA proved useful in estimating the vascularity of hyperechoic lesions in plain US, but was not necessary when estimating vascularity of hypoechoic lesions in plain US images. Although all 10 hyperechoic nodules were diagnosed as isovascular nodules by CEUS, 8 were diagnosed as hypovascular nodules and 2 as vascular spot in hypovascular nodules by USDSA. Vascularity index of the 10 nodules ranged from 0.00 to 0.88 and was less than 1.00 in all cases. Vascularity index of the vascular spot indicated by USDSA was higher than that of other nodular lesions. These findings demonstrate the hemodynamic heterogeneity of tumors.